616 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
VENATION OF LEAVES. 
In connection with the greater degree of dimorphism shown by 
the leaves of patashte, there is another difference. The blades of 
patashte leaves not only have broader outlines, but show a different 
arrangement of the veins. The venation of patashte is palmate, 
while that of cacao is pinnate. Instead of a single strong primary 
vein or midvein which gives rise to all of the secondary veins, as 
in cacao, the leaf of patashte has several larger secondary veins, 
inserted directly on the basal pulvinus, which is broadened at the 
end to receive them. The structure of the pulvinus and the arrange- 
ment of the veins are shown in plates 48 and 49. With several of 
the veins in direct relation with the pulvinus, one side of the leaf 
may be raised in advance of the other whereas in cacao the entire 
leaf blade must be moved as a unit. 
The palmate venation of patashte suggests a comparison with the 
related genus Herrania, which has palmately divided leaves, some- 
what like those of the horse-chestnut (Aesculus). But there is 
little agreement with Herrania in other respects. The leaves of 
patashte might also be compared with those of some of the American 
species of Sterculia, such as S. carthaginensis. 
POSITIONS OF INFLORESCENCES. 
Another very striking contrast is that cacao flowers are borne on 
the oldest wood, while the flowers of patashte are confined to the 
new growth, as shown in plates 50 and 51. It is not merely that 
cacao is caulocarpous while patashte is cladocarpous, but the very 
extremes of these habits are shown. The cacao tree flowers most 
abundantly’ and persistently on the main trunk itself, and more 
sparingly on the old wood of the larger and smaller branches, but 
never on the new growth. The contrast could not be made more 
complete; the cacao tree begins flowering at the base of the main 
trunk and never bears its flowers in the places where all of the flowers 
of patashte are borne, at the ends of the growing branches with the 
new leaves. 
In the cacao tree the positions of the flowers in relation to the 
leaf scars may be studied, although the leaves fall long before the 
inflorescences appear. It has been learned in this way that the 
first inflorescences usually arise somewhat above the middle of the 
leaf scar, in the same relative position as the inflorescence of the 
patashte. But inflorescences that seem to be truly adventitious are 
found in other positions, and especially around the swollen bases of 
EXPLANATION OF PLATES 50, 51.—PI. 50, inflorescences of patashte at flowering stage, with new 
leaves near the growing ends of branches. Pl, 51, trunk of cacao tree, producing flowers and fruits 
directly from the old wood, contrasting thus with patashte, as shown in plate 50. Pl. 50 natural size; pl. 
51 reduced. 
